﻿using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.ServiceProcess;
using System.Text;
using System.Threading;

namespace GPSTK201ProtocolListenerWindowsService
{
    // State object for reading client data asynchronously
    public class StateObject
    {
        // Client socket.
        public Socket workSocket = null;
        // Size of receive buffer.
        public const int BufferSize = 512;
        // Receive buffer.
        public byte[] buffer = new byte[BufferSize];
    }


    public partial class GPSTK201ProtocolListenerWindowsService : ServiceBase
    {

        //Message Queue
        [Serializable]
        public class GPSMessageQueue
        {
            public string Imei;
            public GPSTrackingDBV2.Entities.TrackDataLastLocation TrackDataLastLocationEntity;
        }

        string _MessageQueueName = @Properties.Settings.Default.MessageQueueName;
        
        public const int BufferSize = 512;
        // Thread signal.
        public static ManualResetEvent allDone = new ManualResetEvent(false);
        Thread TCPListenerThread = new Thread(StartListening);
        public static bool IsThreadAlive = true;


        // Enum Field
        enum MessageField
        {
            TerminalID = 0, 
            PhoneCentral = 1, 
            Protocol = 2, 
            DateTime = 3,
            Status = 4, 
            Latitude = 5, 
            Hemisphere1 = 6, 
            Longitude = 7, 
            Hemisphere2 = 8, 
            Speed = 9, 
            Imei = 16
        }


        public GPSTK201ProtocolListenerWindowsService()
        {
            InitializeComponent();
        }

        protected override void OnStart(string[] args)
        {
            try
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Info("--- GPS Tracking Server Start Listening TK201 V1 ---", "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Info("IP: " + System.Net.Dns.GetHostName(), "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Port: " + Properties.Settings.Default.Port.ToString(), "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Max Connections: " + Properties.Settings.Default.MaxConnections.ToString(), "TK201");
                
                IsThreadAlive = true;
                TCPListenerThread.Start();
            }
            catch (Exception ex)
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error..... Message:" + ex.Message + " StackTrace:" + ex.StackTrace, "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("TK201 Server is DOWN", string.Empty);
            }
        }

        protected override void OnStop()
        {
            IsThreadAlive = false;
            GPSTrackingDBCustom.Log.WindowsServiceLog.Warning("--- GPS Tracking Server TK201 Is DOWN ---", "TK201");
        }

        public static void StartListening()
        {
            IPEndPoint ep = new IPEndPoint(IPAddress.Any, Properties.Settings.Default.Port);

            // Create a TCP/IP socket for listner.
            Socket listenerSock = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);

            // Bind the socket to the endpoint and wait for listen for incoming connections.
            try
            {
                listenerSock.Bind(ep);
                listenerSock.Listen(Properties.Settings.Default.MaxConnections);

                while (IsThreadAlive)
                {
                    try
                    {
                        // Set the event to nonsignaled state.
                        allDone.Reset();

                        // Start an asynchronous socket to listen for connections.
                        GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Waiting for a connection TK201.....", "TK201");
                        listenerSock.BeginAccept(new AsyncCallback(AcceptCallback), listenerSock);

                        // Wait until a connection is made before continuing.
                        allDone.WaitOne();
                    }
                    catch (Exception ex)
                    {
                        GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error Waiting for a connection..... Message:" + ex.Message + " StackTrace:" + ex.StackTrace, "TK201");
                        listenerSock.Shutdown(SocketShutdown.Both);
                        listenerSock.Close();
                    }

                }

            }
            catch (Exception ex)
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error..... Message:" + ex.Message + " StackTrace:" + ex.StackTrace, "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("TK201 Server is DOWN", string.Empty);
            }
        }

        public static void AcceptCallback(IAsyncResult ar)
        {
            try
            {
                // Signal the main thread to continue.
                allDone.Set();

                // Get the socket that handles the client request.
                Socket listener = (Socket)ar.AsyncState;
                Socket handler = listener.EndAccept(ar);

                // Create the state object.
                StateObject MessageDevice = new StateObject();
                MessageDevice.workSocket = handler;
                handler.BeginReceive(MessageDevice.buffer, 0, StateObject.BufferSize, 0, new AsyncCallback(ReadCallback), MessageDevice);
            }
            catch (Exception ex)
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error..... Message:" + ex.Message + " StackTrace:" + ex.StackTrace, "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("TK201 Server is DOWN", string.Empty);
            }
        }

        public static void ReadCallback(IAsyncResult ar)
        {
            // Retrieve the state object and the handler socket
            // from the asynchronous state object.
            StateObject MessageDevice = (StateObject)ar.AsyncState;
            Socket handler = MessageDevice.workSocket;

            // Read data from the client socket.
            int bytesRead = handler.EndReceive(ar);

            try
            {
                //No Message 
                if (bytesRead <= 0)
                {
                    GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Disconnected... gps device. No Message", "TK201");
                    handler.Shutdown(SocketShutdown.Both);
                    handler.Close();

                    return;
                }

                //Process Message Hande Held
                string Message = System.Text.UTF8Encoding.UTF8.GetString(MessageDevice.buffer).Replace("\0", "");

               
                    GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Message Device: " + Message, "TK201");
                    string[] MessageArray = Message.Split(new char[] { ',' });

                    string DeviceID = MessageArray[(int)MessageField.Imei].Replace("imei:","");
                    string DeviceDateTime = MessageArray[(int)MessageField.DateTime];
                    string DeviceLatitude = MessageArray[(int)MessageField.Latitude];
                    string DeviceLongitude = MessageArray[(int)MessageField.Longitude];
                    string DeviceSpeed = MessageArray[(int)MessageField.Speed];

                    double Speed = Convert.ToDouble(DeviceSpeed) * 1.852; //Converto knots to KM   1KM = 1.852
                
                    //Convert NMEA
                    //Convert Lat.
                    int LatDegree = Convert.ToInt32(DeviceLatitude.Substring(0, 2));
                    double LatMinute = Convert.ToDouble(DeviceLatitude.Substring(2));

                    LatMinute = LatDegree + (LatMinute / 60);

                    //Convert Long.
                    int LongDegree = Convert.ToInt32(DeviceLongitude.Substring(0, 3));
                    double LongMinute = Convert.ToDouble(DeviceLongitude.Substring(3));

                    LongMinute = LongDegree + (LongMinute / 60);
                    LongMinute = LongMinute * -1;

                    //Insert to Database
                    GPSTrackingDBV2.Entities.TrackData TrackDataEntity = new GPSTrackingDBV2.Entities.TrackData();
                    try
                    {
                        GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Inserting track message to database ...", "TK201");
                        GPSTrackingDBV2.Entities.TrackDataLastLocation TrackDataLastLocationEntity = new GPSTrackingDBV2.Entities.TrackDataLastLocation();

                        TrackDataLastLocationEntity.GpsImei = TrackDataEntity.GpsImei= DeviceID;
                        TrackDataLastLocationEntity.DateTime = TrackDataEntity.DateTime = DateTime.Now;
                        TrackDataLastLocationEntity.Latitude = TrackDataEntity.Latitude = LatMinute;
                        TrackDataLastLocationEntity.Longitude = TrackDataEntity.Longitude = LongMinute;
                        TrackDataLastLocationEntity.Heading = 0;
                        TrackDataLastLocationEntity.Speed = Speed;

                        GPSTrackingDBV2.Data.DataRepository.TrackDataProvider.Insert(TrackDataEntity);

                        //Update last location  
                        GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Updating last track message location to database ...", "TK201");
                        try
                        {
                            GPSTrackingDBV2Custom.Data.DataRepository.TrackDataLastLocationProvider.UpdateOrInsert(TrackDataLastLocationEntity);
                        }
                        catch (Exception ex)
                        {
                            GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error Updating last track message:" + ex.Message, "TK201");
                            // Disconnect Hand Held                            
                            Send(handler, Encoding.ASCII.GetBytes("Error Updating>" + ex.Message));
                        }


                        //Notifier Queue
                        if (Properties.Settings.Default.EnabledMessageQueueName)
                        {
                            SendMQ(TrackDataLastLocationEntity);
                        }



                    }
                    catch (Exception ex)
                    {
                        GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error Inserting track message:" + ex.Message, "TK201");
                        // Disconnect Hand Held                            
                        Send(handler, Encoding.ASCII.GetBytes("Error Inserting>" + ex.Message));
                    }

                    // Disconnect Hand Held                      
                    handler.Shutdown(SocketShutdown.Both);
                    handler.Close();
                    GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Disconnected... gps device.", "TK201");
                    //Send(handler, Encoding.ASCII.GetBytes("OK"));
                
            }
            catch (Exception ex)
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error message invalid:" + ex.Message, "TK201");
                // Disconnect Hand Held                    
                handler.Shutdown(SocketShutdown.Both);
                handler.Close(); 

                //Send(handler, Encoding.ASCII.GetBytes("Message Invalid"));
            }

        }

        private static void Send(Socket handler, byte[] MessageSend)
        {
            try
            {
                // Begin sending the data to the remote device.               
                handler.BeginSend(MessageSend, 0, MessageSend.Length, 0, new AsyncCallback(SendCallback), handler);
            }
            catch (Exception ex)
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error..... Message:" + ex.Message + " StackTrace:" + ex.StackTrace, "TK201");
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("TK201 Server is DOWN", "TK201");
            }
        }

        private static void SendCallback(IAsyncResult ar)
        {
            // Retrieve the socket from the state object.
            Socket handler = (Socket)ar.AsyncState;
            try
            {
                // Complete sending the data to the remote device.
                //int bytesSent = handler.EndSend(ar);
                GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Disconnected... gps device.", "TK201");
                handler.Shutdown(SocketShutdown.Both);
                handler.Close();

            }
            catch (Exception ex)
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Error SendCallBack..... " + ex.Message, "TK201");
                handler.Shutdown(SocketShutdown.Both);
                handler.Close();
            }
        }

        public static void SendMQ(GPSTrackingDBV2.Entities.TrackDataLastLocation trackDataLastLocationEntity)
        {

            string MessageQueueName = @Properties.Settings.Default.MessageQueueName;
            if (System.Messaging.MessageQueue.Exists(MessageQueueName))
            {
                System.Messaging.MessageQueue MessageQueue = new System.Messaging.MessageQueue(MessageQueueName);
                try
                {
                    GPSMessageQueue GPSMessageQueue = new GPSMessageQueue()
                    {
                        Imei = trackDataLastLocationEntity.GpsImei,
                        TrackDataLastLocationEntity = trackDataLastLocationEntity
                    };

                    MessageQueue.Send(GPSMessageQueue);
                    GPSTrackingDBCustom.Log.WindowsServiceLog.Info("Message Queue: OK", "TK201");

                }
                catch (System.Messaging.MessageQueueException ex)
                {
                    GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Message Queue Exception:" + ex.Message, "TK201");
                }
                finally
                {
                    MessageQueue.Close();
                }
            }
            else
            {
                GPSTrackingDBCustom.Log.WindowsServiceLog.Error("Message Queue Exception: Queue not found!", "TK201");
            }
        }

    }
}
